Think of this as a primer for all of those, like the sufferers of the awful disease Chronic Fatigue Syndrome, who need to be heard in Washington and aren’t. Silence has a price.

There are two branches of lobbying in Washington. The first is big lobbying, with big money making big campaign contributions. The second is everyday lobbying, which is quietly effective, scarcely organized and part of the fabric of decision-making. Call it informational lobbying.

Congress cannot be expected to be knowledgeable about a myriad of issues, and this is where the lobbyists perform their often more innocent function. Simply, they know stuff. Their advice isn’t always objective, but it’s informed.

Certainly Congress has the best research available, through the Congressional Research Service of the Library of Congress and all the executive branch agencies. But it’s a lot easier to call a friend, where a question can be asked and answered in the vernacular: “Joe, what’s the story on the helium shortage?” It can be argued that, at this level, lobbying is not suspect but efficient.

Proximity is a force in Washington, familiarity a lever. There are no fingerprints; it’s how the system works. A chance meeting in a restaurant can change the course of policy; influence a congressional opinion about something obscure but important, like the Endangered Species Act, which is now receiving attention on its 40th anniversary.

The indictment of this informal lobbying regime is not that it exists and works, but that if you aren’t at the table, you won’t be heard. Woe betide those who don’t have a lobbying operation, however modest, in Washington.

The lobby-less must suffer in obscurity: No lobby means no input. No conversation after church or at a kid’s soccer game means no information is spreading about actions and decisions that will have impact down the line.

Make no mistake, proximity means a lot in the informing of government. A few casual words will often trump a great academic study.

For the past several years, I’ve taken a keen interest in Chronic Fatigue Syndrome, also known as Myalgic Encephalomyelitis. It’s a disease associated with the suppression, for reasons unknown, of the immune system. To get it is to contract a life sentence of daily suffering, often so severe that patients can be bedridden for years. They think of themselves as “the damned.”

This community has issues with the federal government; specifically with the Department of Health and Human Services, which has oversight of the National Institutes of the Health. Yet the advocates for CFS — many of them superbly articulate — aren’t heard in Washington.

This is very clear, at the moment, when the department, acting through the NIH, has signed a contract with the Institute of Medicine to develop “clinical diagnostic criteria” for CFS.

This has so enraged the top tier of 35 doctors and researchers in the field that they — risking good relations and future research funding — have written to HHS Secretary Kathleen Sibelius, imploring her to halt this folly. The Institute of Medicine doesn’t have expertise in this field, according to the CFS doctors.

Most CFS specialists agree that an effective definition of the disease, known as the Canadian Consensus Criteria, is working fine and should be retained. Confusion and expense from Washington aren’t needed. A wrong definition can be destructive to research, treatment and patient well-being. It will have consequences.

But the protests may have come too late, as knowledge of what the NIH was up to came too late.

To me, this bureaucratic shuffle by HHS is an example of the dangers of not having a presence in Washington. Government responds to pressure. No presence, no pressure, no result — or worse, a bad result.

You don’t need huge money to lobby. Effective lobbying is often a case of simply being there and being known to be there. Walking the halls of Congress catches the attention not only of Congress, but also wayward federal departments and the media.